You are in the market for a new copier for your office, a you have narrowed the search down to models. The energy-efficient model sells two for $800 and will save you $60 at the end of each of the next five years in electricity costs. The standard model has features similar to the energy- efficient model but provides no future savings in electricity costs. It is priced at only $525. Assuming your opportunity cost of funds is 5 percent, which copier should you purchase